A street circuit in NY city would be difficult to realize (just as with SF), but to simply have it in NJ with a NY backdrop is satisfactory, it is much like the Montreal GP- it doesn't run through Montreal at all, but it is right next to the city (it also just happens to be a 'street circuit' in terms of track layout). And I'm with JT, call it the NJGP not NYGP, it's only accurate and it's more blue collar!
Interesting to see the track layout in Google maps- the only thing I would suggest is to add some temporary chicanes where possible to eliminate too many 90 degree corners.